| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method which exhibits excellent NO<SB>x</SB>removal performances and durability even when it is applied to an exhaust gas containing sulfur dioxides and can efficiently remove NO<SB>x</SB>from the exhaust gas even when a reducing agent is used in a small amount, and to provide an apparatus therefore. <P>SOLUTION: In the method, the reducing agent used comprises methanol and/or dimethyl ether, the denitrification catalyst used comprises proton-type βzeolite. The denitrification catalyst is divided into at least two layers arranged in series. The reducing agent is added to the respective catalyst layers 1 and 2 from the upstream of each layer by means of reducing agent addition means 3 and 4. In one embodiment, the nitrogen oxide concentrations of the exhaust gases upstream of the respective catalyst layers 1 and 2 are measured, and the reducing agent is added to the respective layers in controlled amounts. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
